Apparatus for taking fluid samples



June 6, 1939. J. B; CLARK APPARATUS FOR TAKING FLUID SAMPLES Filed May 31, 1938 v Y RC E N .m W fl AT mw M 8 o m Patented June 19 39 s PATENT OFFICE APPARATUS FOR-TAKING FLUID SAMPLES Joseph Baldwin Clark, Tulsa, Okla, assignor to ,Stanolind Oil and Gas Company, Tulsa, Okla d a corporation of Delaware Application May 31, 1938, Serial No. 210,900

. 14 Claims.

This invention relates to an apparatus for taking samples of fluid, and more particularly to bottom hole sampling device for obtaining samples of the fluid in a deep well under the conditions existing therein.

In the study of problems relating-to subterranean reservoirs of oil and gas, it is frequently desirable to have data-which can only be obtained by testing samples of these fluids taken from the reservoir in as near their original state as. is possible. In all high pressure oil reservoirs, there exists both oil and gas; the gas, however, is usually in solution in the oil at these pressures. As the pressure is released from l5 the liquid oil-gas mixture, the gas escapes, so that on the surface of the ground, both liquid and gaseous material are produced. However, at the tailed description, read in connection with the drawing, in which:

Figure l is a vertical section through the upper portion of a preferred embodiment of my invention;

Figure 2 is a vertical section through the middle portion of the same preferred embodiment;

Figure 3 is a vertical section through the lower portion thereof; and

Figure 4 is a vertical section through the lower. 10 portion thereof showing this portion in inverted position and equipped with a transfer head through which the sample can be removed.

The description of my invention will proceed with-'special reference to the preferred specific surface, the ratio between gas and oil produced does not necessarily duplicate the ratio between gas and oil co-existing in a single phase in the high pressure reservoir. Thus in order to find out the actual nature of the materials existing in the reservoir, it becomes necessary to obtain a sample of the single-phase oil-gas mix- 5 ture from the bottom of the oil well; rather than from its surface valves and piping; and to confine this sample so that it may be removed from the well for testing without any loss (or gain) of material.

pose but none of them is completely satisfactory for a number of reasons Among these have been the diillculty ininsuring the taking of a representative sample at the desired location and in retaining the sample without loss of material in the sampler until it has been raised to the surface of the earth and is ready for transfer to a bomb or other testing apparatus. These difilculties may be easily understood when it is real- 40 ized that oil wells having a depth in excess of 10,000 feet are now quite common and that the reservoir pressure at which the sample must be retained often exceeds 2500 pounds per square inch.

It is ,an object apparatus for taking samples of the fluid in a well under the pressure and temperature p'revailing therein; ,7 Another object is to provide a self-contained bottom hole sampling device con- ,50 taining electrical means for sealing a representa-vtive fluid, sample therein at a predetermined time. A further object is to provide'a bottom hole sampler which will retain a sample athigh pressure without danger o'fleakage. Further ob- Fwleew'wfll be pp nt om the following deof my invention to provide an seal.

embodiment thereof illustrated in Figures 1, 2 and 3, in which headpiece I0 having its upper] portion shaped to receive a loop on the end of cable II is screwed into the upper portion of tubular section l2 so as to make a pressure-tight 20 Attached to the lower end of section I! by means of cooperating threads is a coaxial section l3 having the same internal and external diameters and an integral partition wall M, which is provided with an axial bore l5. Bolt l6 having a smaller diameter than bore l5 but an en-' larged portion ll thereon is inserted through bore IE but is held out of electrical contact with partition wall M and centered in bore l5 by means of insulating discs I! and i9 on opposite sides of wall It. Resting on upper disc i9 is a somewhat smaller disc 20 of conducting material, and the assembly is held in place by means of washer 2i and nut 22. Integral with bolt IE but extending below enlarged portion I1 is a downwardly-extending portion 23 having slidably mounted thereon a collar 24 and disc '25 of conducting material. A compression spring 26 urges disc 25 downward along portion 23 but this downward travel is limited by pin 21 through portion 23. a

This construction provides a pressure-tight electrical connection between disc 25 and disc 20.

Resting upon disc 20 is a compression spring 28, upon which rest a number of single-cell dry batteries 29 of a type commonly used in flash- 5 lights placed above each other so that they are in series. An insulating sleeve 30 prevents inadvertent contact between spring 28 and section ll. Spring-28 serves two essential functions:

first, it provides an electrical connection between disc 20 and batteries 29; and second. it urges batteries 2.9 and time switch assembly ll upward against the'bottom of headpiece II- and thus holds them in position.

Time switch assembly 3i consists essentially of 5 a member 32 having circular enlarged portions 33 and 34 on its upper and lower ends, respectively, which is contained within tubular section l2 with a sliding fit. A clock mechanism 35, which may be for example an ordinary wrist watch with its crystal and hands removed, is mounted, preferably in rubber, on member 32 by means of clamps 36 and 31. A disc sector 38 made of insulating material having a cutout portion 39 is mounted on the clock in place of one of the hands, preferably the minute hand, so that it is slowly rotated thereby. A spring contact member 40, which is mounted upon the upper terminal 4| of an-insulated connection 42 through enlarged portion 34 having a lower terminal 43 resting upon positive terminal 44 of the uppermost of batteries 29, bears upon the disc sector 38 in such a way that it is normally held out of contact with contact member 45, which is mounted on member '32. However, when disc sector 38 has been rotated by clock mechanism 35 until cutout portion 39 registers with spring contact member 40, the latter springs into contact with member 45, thus placing positive battery terminal 44 in electrical contact with member 32, which is grounded to tubular member l2 through enlarged portions 33 and 34 and through capscrew 46 on the upper surface of portion 33. From the above detailed description it is apparent that I have provided an improved time switch whereby the batteries 29 may be placed in electrical contact with tubular member l2 at any predetermined time without the passage of electrical current through clock mechanism 35.

Attached to the lower portion of member I 3 by means of cooperating threads and coaxial thereto is tubular member 41, whose lower portion has a somewhat smaller inside diameter than its upper portion, thus forming a shoulder 48, upon which rests a solenoid 49 having windings 50 and an axial cylindrical passage 5| therethrough. One terminal of solenoid windings 50 is grounded to member 41 and the other terminal 52 extends upwardly through tubular insulator 53 and contacts disc 25. An electrical circuit is thus completed so that solenoid windings 50 are energized when out out portion 39 of disc 38 registers with contact member 40, the circuit running from positive terminal 44 of batteries 29 through insulated connection 42, contact members 40 and 45, member 32, enlarged portions 33 and 34 and capscrew 46, and tubular members l2, l3 and 41 to solenoid windings 50 and from theother terminal 52 of these windings through disc 25, bolt i6, disc 20'and-spring 28 to the bottom or negative terminal of batteries 29.

Armature 54, which is elongated in shape, is slidably mounted within solenoid passage 5| and has connecting axial and transverse drill holes 55 for'the passage of fluid therethrough. Im-

mediately above armature 54 and also slidably mounted within passage 5| is solenoid stop 56, which is supported therein by means of the enlarged portion 51 bearing on solenoid 49 andhas an axial drill hole 58. Armature 54 is adjustably attached at its lower end to armature toggle link 59 by means 'of threads so that when solenoid windings 59 are not energized and the apparatus is ready for use, as shown, there is a small gap between armature 54 and solenoid stop 56. When solenoid windings 50 are energized by means of the circuit hereinabove described armature 54 and toggle link 59 are raised a shortdistanceby the magnetic energy of the solenoid 49.

Externally threaded screen nipple 60, having a number of holes 6| therethrough covered by screen 62, which is held in place by split ring retainers 63, is attached to the lower end of member 41, by means of the internal threads on the latter, and also supports a special sleeve 64, which is disposed within member'41, by means of internal threads at its upper end. The lower portion 65 of sleeve 64 is formed with an axial opening 66 therethrough for the reception of trigger guide rod 61, which has longitudinal flats 68 formed thereon so as to allow the passage of fluid from the interior of nipple 69 to the interior of member 41, and to aid in preventing sticking of rod 61 in opening 66. Guide rod 61 is attached at its upper end to trigger support member 69, which bears toggle support screw 10 and two oppositely placed links 1| attached at their upper ends to the lower outer portions of two trigger sear links 12 by means of pins. Trigger sear links 12 are both pivoted at the lower end of armature toggle link 59 and are shaped so that when in cocked position, as shown, their upper outer portions engage retaining shoulder 13, which is preferably a strand of wire or similar material placed in an appropriate groove within sleeve 64 so that it may be easily replaced in the field. This arrangement is such that only a small amount of energy exerted to raise armature 54 and armature toggle link 59 will allow trigger sear links 12 to pass over retaining shoulder 13. The sensitivity of this trigger assembly can be varied by threading toggle support screw 19 in or out. The lower screw 10 and therefore the inner portions 01' links 12 are, themore stable the trigger assembly is to shock and also the more pull by armature 54 is required to release it.

Long sample tube 14 is threaded on the lower portion of nipple 60 in such a way that outlet port member 15 is retained in position by shoulder 16 within tube 14 and gasket 11. By this arrangement increased pressure in sample chamber 18 below outlet port member 15 causes the latter to compress gasket 11 further so that the pressure within gasket 11 exceeds the pressure in sample chamber 18 and a very effective seal is obtained. Outlet valve stem 19 carrying outlet valve 30 is slidably supported within member 15 and is attached at its upper end to trigger guide rod 61. Surrounding valve stem 19 is compression spring 8| which bears on member 15 and on spring seat 82 on the upper end of valve stem 19. A swivel joint 83 is provided between valve stem 19 and valve 80, but the latter is kept in alignment and prevented from vibrating by means of resilient disc 84, which is preferably made of an oil-resisting synthetic rubber. Both valve 89 and valve seat 85 in member 15 are provided with knife edges 86 and 81, respectively, and valve seat 85 is also recessed for the reception of gasket 88, which is held in position by friction, preferably with the aid of circumferential grooves in member 15.

Sample tube 14 is also provided internally with a downwardly-facing shoulder 89 against which hammer rod support 90, sleeve 9| and inlet port member 92 are'held by means of nipple 93 and gasket 94, the seal between nipple 93 and member 92 being of the same type hereinabove described in connection with nipple 60 and member 15. The construction of the inlet valve assembly, in-

' eluding inlet valve 95 having knife edge 96, inlet valve stem 91, knife edge 98 and gasket 99, is the same as that of the outlet valve assembly except that no compression spring is provided so that valve 95 acts as a ch'eck valve to allow fluid to flow into but not out of sample chamber I8.

Hammer rod I having an enlarged lower portion IOI and an axialbore I02 in its upper portion a trigger ball seat I communicating with bore I02 containing trigger ball I05, which is adapted to cooperate with a notch I0| in support 90 to hold hammer rod I00 in the position shown against the action of spring I04 when reduced 'portion I08 of trigger rod I09 is inserted a. sufficient distance into bore I02. Trigger rod I09 is attached to outlet valve 80 by means of rod H0 and turnbuckle III, which is held in axial position by arms II2. Footpiece II3, which is attached to nipple 93 by cooperating threads, is provided with a number of openings II 4, and carries a screen I24 which is held in position by screen retaining ring I25.

In using my improved sampling device to obtain a sample of the fluid in a deep well, headpiece I0 is removed, time switch assembly 3I is removed from tubular section I2, clock mechanism 35 is set so that contact will be made between members 40 and 45 at a predetermined time suflicient to allow the device to be lowered into a well to the depth at which it is desired to take a sample, and time switch assembly 3I and headpiece I0 are returned to their respective positions. The sampling device is then lowered into the well by means of cable I I. During the lowering operation the fluid in the well enters sample chamber 18 through openings H4 and inlet port member 92, valve 95 being lifted by the pressure of the incoming fluid. Since outlet valve 80 is held open, fluid continuously flows from chamber I8 through outlet port member I5 and out the holes 5| in is raised and rapidly lowered several times to purge sample'chamber I8 of well fluid received therein during the lowering of the device so that a representative sample of the well fluid at the desired point may be obtained.

When the predetermined time for taking the sample has arrived, contact is automatically made between members 40 and 45, thus energizing solenoid windings 50 and raising armature 54 a short distance as hereinabove described. This movement raises armature toggle link 59 and allows trigger sear links I2 to pass over retaining .trigger ball I05 is released from contact with reduced portion I08 so that it moves out of notch I0I, thereby allowing hammer rod I00 to be propelled by spring I04 against the top of inlet valve 95, which assists in obtaining a perfect seal between valve 95 and inlet portmember 92. Furthermore hammer rod I00 is thereafter held against valve 95 by spring in so as to hold it'in place.

It is apparent from the above that I have provided an improved sampling device which is particularly suitable for obtaining samples of oil well fluids underbottom hole temperatures and pressures and retaining them unaltered and without leakage until they are to be tested.

In my preferred method of transferring the sample to a testing bomb, the device is inverted,

footpiece H3 is removed, spring seat H5 and.

spring II5 are inserted in nipple .93, and transfer head I I1 is screwed on nipple 93 to make a pressure-tight joint as shown in Figure 4. Spring seat II5 slides freely within nipple 93 and bears upon the end of valve stem 91, and spring H5 is somewhat stronger than spring I04, so that valve 95 is held in its closed position only by the pressure of the sample within chamber I8. Transfer head I II is provided with a bore I I8 and threads I I9 for connection to a testing bomb (not shown) by means of pressure tube I20 and a bore I2I .and threads I22 for connection with a source oi mercury under pressure by means of pressure into chamber I8 and displace the sample, which I rises and flows through bore H8 and tube I20 to the testing bomb.

In order to prepare my sampling device for another trip down a well, the mercury pressure is -detached,.solenoid stop 51 is removed and armature 54 is depressed until valve 80 is open and toggle link 59 rests upon toggle support screw I0, so that trigger sear links 12 again engage retaining shoulder I3. Since hammer rod I00 is still held in retracted position, trigger rod I 09 enters bore I02 and forces trigger ball I05 into notch I0I, thus locking hammer rod I00 in that position. Solenoid stop 51 is replaced and members I3 and 41 again attached. Transfer head III, spring H6 and spring seat II5 are then-removed from nipple 93 and replaced by footpiece I I3. Finally'headpiece I0 is removed, time switch assembly 3I and discharged batteries 29 are withdrawn, new batteries are inserted, clock mechanism 35 is set, and time switch assembly 3| and headpiece I0 are replaced in their respective positions. The sampling device 'is then ready to be lowered into a well for;the taking of another sample. v

While I have described my invention in connection with a specific embodiment thereof, I do not inlet port, ,a valve in said outlet port, means forurging said valve to its closed position, means for retaining said valve in its open position against the action of said urging means, means actuated by an electric current for renderin said valve-retaining means inoperati e and means for supplying an electric current 0 said lastmentioned means at a desired time.

2. Apparatus for taking samples of fluid from a well comprising a sample chamber having inlet and outlet ports, means for preventing back flow of fluid from said chamber through said inlet port, a valve in said outlet port, means actuated by an electric current for closing said valve and means for supplying an electric current to said last-mentioned means at a desired time.

3. Apparatus for taking samples of fluid from a well comprising a sample chamber having inlet and outlet ports, means for preventing back flow of fluid from said chamber through said inlet port, a valve in said outlet port, means actuated by a solenoid when an electric current is passed therethrough for closing said valve, and means for passing an electric current through said solenoid at a predetermined time.

4. Apparatus for taking samples of fluid from a well comprising a! sample chamber having inlet and outlet ports, a check valve adapted to prevent back flowof fluid from said chamber through said inlet" port, a valve in said outlet port, means actuated by an electric current for simultaneously closing said outlet valve and locking said check valve in its closed position and means for supplying an electric current to said last-mentioned means at .a desired time.

5. Apparatus for taking samples of fluid from a well comprisingasample chamber having inlet and outlet ports, a check valve adapted to premeans for rendering said valve-retaining meansvent back flow of fluid from said chamber through said inlet port, a valve in said outlet port, a clock mechanism, means actuated by an elec tric current for simultaneously closing said outlet valve and locking said check valve in its closed position and means for supplying an electric current to said last-mentioned means at a desired time determined by the setting of said clock mechanism.

6. In a bottom hole sampling device having a sample chamber providedwith inlet and outlet ports and inlet and outlet valves controlling flow of fluid through said ports, the combination comprising means for urging said outlet valve toward its closed position, means for retaining said outlet valve in its open position against the action of said urging means, a solenoid, means actuated by said solenoid when an electric current is supplied thereto for rendering said valve-retaining means inoperative, and means for supplying an electric current to said solenoid at a predetermined time.

7. The combination of claim 6 wherein said inoperative includes an elongated armature slidably mounted within said solenoid along the axis thereof.

8. The combination of claim 6 wherein said current-supplying means includes a source of electromotive force, a clock mechanism and means actuated by said clock mechanism for allowing electric current from said source of electromotive force to flow to said solenoid.

9. The combination of claim 6 wherein said inlet valve is adapted to prevent back flow of fluid through said inlet port and including means responsive to the closing of said outlet valve for sealing said inlet valve in its closed position.

10. In a bottom hole sampling device. having a sample chamber provided with-inlet and outlet ports, and outlet valve, and an inlet valve adapted port from said chamber, the combination commeans, and means actuated by said valve-closing means for rendering said retaining means inoperative, whereby said hammer member strikes said inlet valve and efiectively seals said inlet port.

11. The combination of claim 10 wherein said inlet port is provided with a valve seat having a continuous knife edge thereon and a gasket covering said knife edge and said inlet valve is provided with a second continuous knife edge adapted to come in contact with the upper surface of said gasket when said inlet valve is in closed position.

12. A bottom hole sampling device comprising a tubular case, members having valve ports therethrough mounted. within said case and defining a sample chamber therein, valves adapted to close said valve ports, a compressible gasket for each of said members adapted to provide a seal between each of said members and said case, and means whereby fluid pressure within said sample chamber subjects said gaskets to a pressure in excess of said fluid pressure.

13. A bottom hole sampling device comprising a sample chamber provided with inlet 'and outlet ports, a check valve adapted to prevent back flow of fluid from said chamber through said inlet port, an outlet valve adapted to prevent flow of fluid through said outlet port, means for urging said outlet valve toward its closed position, means for retaining said outlet valve in its open position against the action of said urging means, a solenoid having an axial passage therethrough, an armature slidably mounted in said axial passage adapted to move longitudinally therein when an electric current passes through said solenoid, means actuated by said armature for rendering said valve-retaining means inoperative, an electric circuit including a source of electric current, a switch and said solenoid, a clock mechanism adapted to close said swith at a predetermined time, a slidably mounted hammer member adapted to bear upon said check valve when in extended position, means for urging said hammer member into extended position, means for retaining said hammer member in retracted position, and means actuated by said outlet valve for rendering said means for retaining said hammer member inoperative, whereby said outlet valve is closed and said check valve is sealed simultaneously at a predetermined time.

14. A bottom hole sampling device comprising a tubular case, two members having valve ports therethrough slidably mounted within said case and defining a sample chamber therein, a compressible gasket for each of said members adapted to provide a seal between each of said members and said case, means whereby fluid pressure within said sample chamber subjects said gaskets to a pressure in excess of said fluid pressure, a check valve adapted to prevent back flow of fluid from said chamber through one of said valve ports, an outlet valve adapted to prevent flow of fluid through the other of said valve ports, means for urging said outlet valve toward itsclosed position, means for retaining said outlet valve in its open position against the action of said urging means,

a solenoid having an axial passage therethrough, an armature slidably mounted in said axial passage adapted to move longitudinally therein when an electric current passes through said solenoid, means actuated by said armature for rendering said valve-retaining means inoperative, an electric circuit includinga source of electric current, a switch and said solenoid, a clock mechanism adapted to close said switch at a predetermined time, a slidably mounted hammer member adapted to bear upon said check valve when in extended pomtion, means for urging said hammer member into extended pomtion, means for retaining said hammer member in retracted position, and means actuated by said outlet valve for rendering'said means for retaining said hammer member inoperative, whereby said outlet valve is JOSEPH BALDWIN CLARK. 

